/* Copyright Joyent, Inc. and other Node contributors. All rights reserved.
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to
 * deal in the Software without restriction, including without limitation the
 * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
 * sell copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
 * IN THE SOFTWARE.
 */
#ifndef http_parser_h
#define http_parser_h
#ifdef __cplusplus
extern "C"
{
#endif

/* Also update SONAME in the Makefile whenever you change these. */
#define HTTP_PARSER_VERSION_MAJOR 2
#define HTTP_PARSER_VERSION_MINOR 8
#define HTTP_PARSER_VERSION_PATCH 1

#include <stddef.h>
#if defined(_WIN32) && !defined(__MINGW32__) &&                                \
    (!defined(_MSC_VER) || _MSC_VER < 1600) && !defined(__WINE__)
#include <BaseTsd.h>
    typedef __int8           int8_t;
    typedef unsigned __int8  uint8_t;
    typedef __int16          int16_t;
    typedef unsigned __int16 uint16_t;
    typedef __int32          int32_t;
    typedef unsigned __int32 uint32_t;
    typedef __int64          int64_t;
    typedef unsigned __int64 uint64_t;
#else
#include <stdint.h>
#endif

/* Compile with -DHTTP_PARSER_STRICT=0 to make less checks, but run
 * faster
 */
#ifndef HTTP_PARSER_STRICT
#define HTTP_PARSER_STRICT 1
#endif

/* Maximium header size allowed. If the macro is not defined
 * before including this header then the default is used. To
 * change the maximum header size, define the macro in the build
 * environment (e.g. -DHTTP_MAX_HEADER_SIZE=<value>). To remove
 * the effective limit on the size of the header, define the macro
 * to a very large number (e.g. -DHTTP_MAX_HEADER_SIZE=0x7fffffff)
 */
#ifndef HTTP_MAX_HEADER_SIZE
#define HTTP_MAX_HEADER_SIZE (80 * 1024)
#endif

    typedef struct http_parser          http_parser;
    typedef struct http_parser_settings http_parser_settings;

    /* Callbacks should return non-zero to indicate an error. The parser will
     * then halt execution.
     *
     * The one exception is on_headers_complete. In a HTTP_RESPONSE parser
     * returning '1' from on_headers_complete will tell the parser that it
     * should not expect a body. This is used when receiving a response to a
     * HEAD request which may contain 'Content-Length' or 'Transfer-Encoding:
     * chunked' headers that indicate the presence of a body.
     *
     * Returning `2` from on_headers_complete will tell parser that it should
     * not expect neither a body nor any futher responses on this connection.
     * This is useful for handling responses to a CONNECT request which may not
     * contain `Upgrade` or `Connection: upgrade` headers.
     *
     * http_data_cb does not return data chunks. It will be called arbitrarily
     * many times for each string. E.G. you might get 10 callbacks for "on_url"
     * each providing just a few characters more data.
     */
    typedef int (*http_data_cb)(http_parser *, const char *at, size_t length);
    typedef int (*http_cb)(http_parser *);

/* Status Codes */
#define HTTP_STATUS_MAP(XX)                                                    \
    XX(100, CONTINUE, Continue)                                                \
    XX(101, SWITCHING_PROTOCOLS, Switching Protocols)                          \
    XX(102, PROCESSING, Processing)                                            \
    XX(200, OK, OK)                                                            \
    XX(201, CREATED, Created)                                                  \
    XX(202, ACCEPTED, Accepted)                                                \
    XX(203, NON_AUTHORITATIVE_INFORMATION, Non - Authoritative Information)    \
    XX(204, NO_CONTENT, No Content)                                            \
    XX(205, RESET_CONTENT, Reset Content)                                      \
    XX(206, PARTIAL_CONTENT, Partial Content)                                  \
    XX(207, MULTI_STATUS, Multi - Status)                                      \
    XX(208, ALREADY_REPORTED, Already Reported)                                \
    XX(226, IM_USED, IM Used)                                                  \
    XX(300, MULTIPLE_CHOICES, Multiple Choices)                                \
    XX(301, MOVED_PERMANENTLY, Moved Permanently)                              \
    XX(302, FOUND, Found)                                                      \
    XX(303, SEE_OTHER, See Other)                                              \
    XX(304, NOT_MODIFIED, Not Modified)                                        \
    XX(305, USE_PROXY, Use Proxy)                                              \
    XX(307, TEMPORARY_REDIRECT, Temporary Redirect)                            \
    XX(308, PERMANENT_REDIRECT, Permanent Redirect)                            \
    XX(400, BAD_REQUEST, Bad Request)                                          \
    XX(401, UNAUTHORIZED, Unauthorized)                                        \
    XX(402, PAYMENT_REQUIRED, Payment Required)                                \
    XX(403, FORBIDDEN, Forbidden)                                              \
    XX(404, NOT_FOUND, Not Found)                                              \
    XX(405, METHOD_NOT_ALLOWED, Method Not Allowed)                            \
    XX(406, NOT_ACCEPTABLE, Not Acceptable)                                    \
    XX(407, PROXY_AUTHENTICATION_REQUIRED, Proxy Authentication Required)      \
    XX(408, REQUEST_TIMEOUT, Request Timeout)                                  \
    XX(409, CONFLICT, Conflict)                                                \
    XX(410, GONE, Gone)                                                        \
    XX(411, LENGTH_REQUIRED, Length Required)                                  \
    XX(412, PRECONDITION_FAILED, Precondition Failed)                          \
    XX(413, PAYLOAD_TOO_LARGE, Payload Too Large)                              \
    XX(414, URI_TOO_LONG, URI Too Long)                                        \
    XX(415, UNSUPPORTED_MEDIA_TYPE, Unsupported Media Type)                    \
    XX(416, RANGE_NOT_SATISFIABLE, Range Not Satisfiable)                      \
    XX(417, EXPECTATION_FAILED, Expectation Failed)                            \
    XX(421, MISDIRECTED_REQUEST, Misdirected Request)                          \
    XX(422, UNPROCESSABLE_ENTITY, Unprocessable Entity)                        \
    XX(423, LOCKED, Locked)                                                    \
    XX(424, FAILED_DEPENDENCY, Failed Dependency)                              \
    XX(426, UPGRADE_REQUIRED, Upgrade Required)                                \
    XX(428, PRECONDITION_REQUIRED, Precondition Required)                      \
    XX(429, TOO_MANY_REQUESTS, Too Many Requests)                              \
    XX(431, REQUEST_HEADER_FIELDS_TOO_LARGE, Request Header Fields Too Large)  \
    XX(451, UNAVAILABLE_FOR_LEGAL_REASONS, Unavailable For Legal Reasons)      \
    XX(500, INTERNAL_SERVER_ERROR, Internal Server Error)                      \
    XX(501, NOT_IMPLEMENTED, Not Implemented)                                  \
    XX(502, BAD_GATEWAY, Bad Gateway)                                          \
    XX(503, SERVICE_UNAVAILABLE, Service Unavailable)                          \
    XX(504, GATEWAY_TIMEOUT, Gateway Timeout)                                  \
    XX(505, HTTP_VERSION_NOT_SUPPORTED, HTTP Version Not Supported)            \
    XX(506, VARIANT_ALSO_NEGOTIATES, Variant Also Negotiates)                  \
    XX(507, INSUFFICIENT_STORAGE, Insufficient Storage)                        \
    XX(508, LOOP_DETECTED, Loop Detected)                                      \
    XX(510, NOT_EXTENDED, Not Extended)                                        \
    XX(511, NETWORK_AUTHENTICATION_REQUIRED, Network Authentication Required)

    enum http_status
    {
#define XX(num, name, string) HTTP_STATUS_##name = num,
        HTTP_STATUS_MAP(XX)
#undef XX
    };

/* Request Methods */
#define HTTP_METHOD_MAP(XX)                                                    \
    XX(0, DELETE, DELETE)                                                      \
    XX(1, GET, GET)                                                            \
    XX(2, HEAD, HEAD)                                                          \
    XX(3, POST, POST)                                                          \
    XX(4, PUT, PUT)                                                            \
    /* pathological */                                                         \
    XX(5, CONNECT, CONNECT)                                                    \
    XX(6, OPTIONS, OPTIONS)                                                    \
    XX(7, TRACE, TRACE)                                                        \
    /* WebDAV */                                                               \
    XX(8, COPY, COPY)                                                          \
    XX(9, LOCK, LOCK)                                                          \
    XX(10, MKCOL, MKCOL)                                                       \
    XX(11, MOVE, MOVE)                                                         \
    XX(12, PROPFIND, PROPFIND)                                                 \
    XX(13, PROPPATCH, PROPPATCH)                                               \
    XX(14, SEARCH, SEARCH)                                                     \
    XX(15, UNLOCK, UNLOCK)                                                     \
    XX(16, BIND, BIND)                                                         \
    XX(17, REBIND, REBIND)                                                     \
    XX(18, UNBIND, UNBIND)                                                     \
    XX(19, ACL, ACL)                                                           \
    /* subversion */                                                           \
    XX(20, REPORT, REPORT)                                                     \
    XX(21, MKACTIVITY, MKACTIVITY)                                             \
    XX(22, CHECKOUT, CHECKOUT)                                                 \
    XX(23, MERGE, MERGE)                                                       \
    /* upnp */                                                                 \
    XX(24, MSEARCH, M - SEARCH)                                                \
    XX(25, NOTIFY, NOTIFY)                                                     \
    XX(26, SUBSCRIBE, SUBSCRIBE)                                               \
    XX(27, UNSUBSCRIBE, UNSUBSCRIBE)                                           \
    /* RFC-5789 */                                                             \
    XX(28, PATCH, PATCH)                                                       \
    XX(29, PURGE, PURGE)                                                       \
    /* CalDAV */                                                               \
    XX(30, MKCALENDAR, MKCALENDAR)                                             \
    /* RFC-2068, section 19.6.1.2 */                                           \
    XX(31, LINK, LINK)                                                         \
    XX(32, UNLINK, UNLINK)                                                     \
    /* icecast */                                                              \
    XX(33, SOURCE, SOURCE)

    enum http_method
    {
#define XX(num, name, string) HTTP_##name = num,
        HTTP_METHOD_MAP(XX)
#undef XX
    };

    enum http_parser_type
    {
        HTTP_REQUEST,
        HTTP_RESPONSE,
        HTTP_BOTH
    };

    /* Flag values for http_parser.flags field */
    enum flags
    {
        F_CHUNKED               = 1 << 0,
        F_CONNECTION_KEEP_ALIVE = 1 << 1,
        F_CONNECTION_CLOSE      = 1 << 2,
        F_CONNECTION_UPGRADE    = 1 << 3,
        F_TRAILING              = 1 << 4,
        F_UPGRADE               = 1 << 5,
        F_SKIPBODY              = 1 << 6,
        F_CONTENTLENGTH         = 1 << 7
    };

/* Map for errno-related constants
 *
 * The provided argument should be a macro that takes 2 arguments.
 */
#define HTTP_ERRNO_MAP(XX)                                                     \
    /* No error */                                                             \
    XX(OK, "success")                                                          \
                                                                               \
    /* Callback-related errors */                                              \
    XX(CB_message_begin, "the on_message_begin callback failed")               \
    XX(CB_url, "the on_url callback failed")                                   \
    XX(CB_header_field, "the on_header_field callback failed")                 \
    XX(CB_header_value, "the on_header_value callback failed")                 \
    XX(CB_headers_complete, "the on_headers_complete callback failed")         \
    XX(CB_body, "the on_body callback failed")                                 \
    XX(CB_message_complete, "the on_message_complete callback failed")         \
    XX(CB_status, "the on_status callback failed")                             \
    XX(CB_chunk_header, "the on_chunk_header callback failed")                 \
    XX(CB_chunk_complete, "the on_chunk_complete callback failed")             \
                                                                               \
    /* Parsing-related errors */                                               \
    XX(INVALID_EOF_STATE, "stream ended at an unexpected time")                \
    XX(HEADER_OVERFLOW, "too many header bytes seen; overflow detected")       \
    XX(CLOSED_CONNECTION,                                                      \
       "data received after completed connection: close message")              \
    XX(INVALID_VERSION, "invalid HTTP version")                                \
    XX(INVALID_STATUS, "invalid HTTP status code")                             \
    XX(INVALID_METHOD, "invalid HTTP method")                                  \
    XX(INVALID_URL, "invalid URL")                                             \
    XX(INVALID_HOST, "invalid host")                                           \
    XX(INVALID_PORT, "invalid port")                                           \
    XX(INVALID_PATH, "invalid path")                                           \
    XX(INVALID_QUERY_STRING, "invalid query string")                           \
    XX(INVALID_FRAGMENT, "invalid fragment")                                   \
    XX(LF_EXPECTED, "LF character expected")                                   \
    XX(INVALID_HEADER_TOKEN, "invalid character in header")                    \
    XX(INVALID_CONTENT_LENGTH, "invalid character in content-length header")   \
    XX(UNEXPECTED_CONTENT_LENGTH, "unexpected content-length header")          \
    XX(INVALID_CHUNK_SIZE, "invalid character in chunk size header")           \
    XX(INVALID_CONSTANT, "invalid constant string")                            \
    XX(INVALID_INTERNAL_STATE, "encountered unexpected internal state")        \
    XX(STRICT, "strict mode assertion failed")                                 \
    XX(PAUSED, "parser is paused")                                             \
    XX(UNKNOWN, "an unknown error occurred")

/* Define HPE_* values for each errno value above */
#define HTTP_ERRNO_GEN(n, s) HPE_##n,
    enum http_errno
    {
        HTTP_ERRNO_MAP(HTTP_ERRNO_GEN)
    };
#undef HTTP_ERRNO_GEN

/* Get an http_errno value from an http_parser */
#define HTTP_PARSER_ERRNO(p) ((enum http_errno)(p)->http_errno)

    struct http_parser
    {
        /** PRIVATE **/
        unsigned int type : 2;  /* enum http_parser_type */
        unsigned int flags : 8; /* F_* values from 'flags' enum; semi-public */
        unsigned int state : 7; /* enum state from http_parser.c */
        unsigned int
                     header_state : 7; /* enum header_state from http_parser.c */
        unsigned int index : 7;        /* index into current matcher */
        unsigned int lenient_http_headers : 1;

        uint32_t nread;          /* # bytes read in various scenarios */
        uint64_t content_length; /* # bytes in body (0 if no Content-Length
                                    header) */

        /** READ-ONLY **/
        unsigned short http_major;
        unsigned short http_minor;
        unsigned int   status_code : 16; /* responses only */
        unsigned int   method : 8;       /* requests only */
        unsigned int   http_errno : 7;

        /* 1 = Upgrade header was present and the parser has exited because of
         * that. 0 = No upgrade header present. Should be checked when
         * http_parser_execute() returns in addition to error checking.
         */
        unsigned int upgrade : 1;

        /** PUBLIC **/
        void *data; /* A pointer to get hook to the "connection" or "socket"
                       object */
    };

    struct http_parser_settings
    {
        http_cb      on_message_begin;
        http_data_cb on_url;
        http_data_cb on_status;
        http_data_cb on_header_field;
        http_data_cb on_header_value;
        http_cb      on_headers_complete;
        http_data_cb on_body;
        http_cb      on_message_complete;
        /* When on_chunk_header is called, the current chunk length is stored
         * in parser->content_length.
         */
        http_cb on_chunk_header;
        http_cb on_chunk_complete;
    };

    enum http_parser_url_fields
    {
        UF_SCHEMA   = 0,
        UF_HOST     = 1,
        UF_PORT     = 2,
        UF_PATH     = 3,
        UF_QUERY    = 4,
        UF_FRAGMENT = 5,
        UF_USERINFO = 6,
        UF_MAX      = 7
    };

    /* Result structure for http_parser_parse_url().
     *
     * Callers should index into field_data[] with UF_* values iff field_set
     * has the relevant (1 << UF_*) bit set. As a courtesy to clients (and
     * because we probably have padding left over), we convert any port to
     * a uint16_t.
     */
    struct http_parser_url
    {
        uint16_t field_set; /* Bitmask of (1 << UF_*) values */
        uint16_t port;      /* Converted UF_PORT string */

        struct
        {
            uint16_t off; /* Offset into buffer in which field starts */
            uint16_t len; /* Length of run in buffer */
        } field_data[UF_MAX];
    };

    /* Returns the library version. Bits 16-23 contain the major version number,
     * bits 8-15 the minor version number and bits 0-7 the patch level.
     * Usage example:
     *
     *   unsigned long version = http_parser_version();
     *   unsigned major = (version >> 16) & 255;
     *   unsigned minor = (version >> 8) & 255;
     *   unsigned patch = version & 255;
     *   printf("http_parser v%u.%u.%u\n", major, minor, patch);
     */
    unsigned long http_parser_version(void);

    void http_parser_init(http_parser *parser, enum http_parser_type type);

    /* Initialize http_parser_settings members to 0
     */
    void http_parser_settings_init(http_parser_settings *settings);

    /* Executes the parser. Returns number of parsed bytes. Sets
     * `parser->http_errno` on error. */
    size_t http_parser_execute(http_parser *               parser,
                               const http_parser_settings *settings,
                               const char *data, size_t len);

    /* If http_should_keep_alive() in the on_headers_complete or
     * on_message_complete callback returns 0, then this should be
     * the last message on the connection.
     * If you are the server, respond with the "Connection: close" header.
     * If you are the client, close the connection.
     */
    int http_should_keep_alive(const http_parser *parser);

    /* Returns a string version of the HTTP method. */
    const char *http_method_str(enum http_method m);

    /* Return a string name of the given error */
    const char *http_errno_name(enum http_errno err);

    /* Return a string description of the given error */
    const char *http_errno_description(enum http_errno err);

    /* Initialize all http_parser_url members to 0 */
    void http_parser_url_init(struct http_parser_url *u);

    /* Parse a URL; return nonzero on failure */
    int http_parser_parse_url(const char *buf, size_t buflen, int is_connect,
                              struct http_parser_url *u);

    /* Pause or un-pause the parser; a nonzero value pauses */
    void http_parser_pause(http_parser *parser, int paused);

    /* Checks if this is the final chunk of the body. */
    int http_body_is_final(const http_parser *parser);

#ifdef __cplusplus
}
#endif
#endif
